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排序方式: 共有402条查询结果,搜索用时 15 毫秒
201.
Malmberg Kenneth J.; Zeelenberg Rene; Shiffrin Richard M. 《Canadian Metallurgical Quarterly》2004,30(2):540
E. Hirshman, J. Fisher, T. Henthom, J. Amdt, and A. Passanname (2002) found that Midazolam disrupts the mirror-patterned word-frequency effect for recognition memory by reversing the typical hit-rate advantage for low-frequency words. They noted that this result is consistent with dual-process accounts (e.g., R. C. Atkinson & J. F. Juola, 1974; G. Mandler, 1980; A. P. Yonelinas, 1994) of the word frequency effect for recognition memory (S. Joordens & W. E. Hockley. 2000; L. M. Reder et al.. 2000). The present authors show that this finding is also consistent with a variety of single-process, retrieving effectively- from-memory (REM) models (R. M. Shiffrin & M. Steyvers, 1997), the simplest of which assumes that Midazolam decreases the accuracy with which memory traces are stored. These findings therefore do not discriminate between single- and dual-process models of recognition memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
202.
Camelia Hora Rene Segers Stefan Eichenberger Maurice Lousberg 《Journal of Electronic Testing》2003,19(4):369-376
The ability to achieve and maintain high yield levels is directly dependent on the capability to detect and analyze repetitive failure mechanisms. In this paper, an advanced statistical diagnosis method, using the final wafer test results, is presented. The new method builds on an existing full diagnosis method, and studies the adaptations needed to turn it into an effective and efficient on-line statistical diagnosis approach. The output of the new approach is a (limited) list of suspect locations, which acts as input for further statistical and physical analysis. The experiments performed show the efficiency as well as the limitations of the proposed approach. 相似文献
203.
Dave Louden Alan Handley Rene Lafont Steve Taylor Ian Sinclair Eva Lenz Timothy Orton Ian D Wilson 《Analytical chemistry》2002,74(1):288-294
HPLC, using superheated D20 as the mobile phase, combined with on-line characterization via a combination of diode array UV, 1H NMR, FT-IR spectroscopy, and mass spectrometry has been used for the analysis of a standard of 20-hydroxyecdysone- and ecdysteroid-containing plant extracts. This combination of spectrometers enabled the on-flow collection of UV, 1H NMR, IR, and mass spectra not only for pure 20-hydroxyecdysone (100-400 microg on column) but also the major ecdysteroids present in crude extracts of Silene otites, Silene nutans, and Silene frivaldiskyana. The ecdysteroids unequivocally identified in these extracts included 20-hydroxyecdysone, polypodine B, and integristerone A. 相似文献
204.
205.
Mohamed Slamani Rene Mayer Marek Balazinski 《The International Journal of Advanced Manufacturing Technology》2013,65(9-12):1669-1679
A modelling approach for volumetric error prediction taking into account geometric and servo dynamic errors in a five-axis high-speed machine tool is proposed in this paper. Polynomial functions are used to represent and then predict the geometric errors. A simple second-order transfer function model is used to model and predict the servo dynamic error. The servo dynamic errors are added to the axis position geometric errors and propagated to the tool and workpiece using matrix transformations. The validity of the error integration concept is tested for a XYC three-axis motion trajectory. Two experimental setups are used. The first experimental test used the KGM grid encoder instrument to estimate the parameters of the servo dynamic error models of the X- and Y-axes. The second experimental test used a programmed end point constraint procedure with measurement of the 3D volumetric positioning errors between a point on the tool holder and another fixed to the machine table. The tests involve maintaining the nominal coincidence of these two points whilst exercising the three axes. These last tests are used to estimate the geometric error parameters and also to validate the prediction performance of the integrated geometric and dynamic model. The result shows the effectiveness of the error integration concept. 相似文献
206.
Muda M Gross AW Dawson JP He C Kurosawa E Schweickhardt R Dugas M Soloviev M Bernhardt A Fischer D Wesolowski JS Kelton C Neuteboom B Hock B 《Protein engineering, design & selection : PEDS》2011,24(5):447-454
The strand-exchange engineered domain (SEED) platform was designed to generate asymmetric and bispecific antibody-like molecules, a capability that expands therapeutic applications of natural antibodies. This new protein engineered platform is based on exchanging structurally related sequences of immunoglobulin within the conserved CH3 domains. Alternating sequences from human IgA and IgG in the SEED CH3 domains generate two asymmetric but complementary domains, designated AG and GA. The SEED design allows efficient generation of AG/GA heterodimers, while disfavoring homodimerization of AG and GA SEED CH3 domains. Using a clinically validated antibody (C225), we tested whether Fab derivatives constructed on the SEED platform retain desirable therapeutic antibody features such as in vitro and in vivo stability, favorable pharmacokinetics, ligand binding and effector functions including antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. In addition, we tested SEED with combinations of binder domains (scFv, VHH, Fab). Mono- and bivalent Fab-SEED fusions retain full binding affinity, have excellent biochemical and biophysical stability, and retain desirable antibody-like characteristics conferred by Fc domains. Furthermore, SEED is compatible with different combinations of Fab, scFv and VHH domains. Our assessment shows that the new SEED platform expands therapeutic applications of natural antibodies by generating heterodimeric Fc-analog proteins. 相似文献
207.
Miguel Aguilar Cortest Martha Lilia Dominguez Patifio Antonio Rodriguez Martinez Rene Guardian Tapia Rosa Maria Melgoza Aleman 《化学与化工:英文版》2013,(8):759-766
The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI (the card's printed circuit) which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, Fe, Ag, Au and Pt. 相似文献
208.
Protective effects of coffee against induction of DNA damage and pre‐neoplastic foci by aflatoxin B1
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209.
Octavio García-Depraect Raúl Muñoz Elisa Rodríguez Eldon R. Rene Elizabeth León-Becerril 《International Journal of Hydrogen Energy》2021,46(20):11284-11296
Despite the high prevalence of lactic acid bacteria in dark fermentation (DF) processes, their ecological role is not yet completely elucidated, preventing their systematic use as “helpers” for hydrogen production. The aim of this study was to investigate the microbial community structure of a lactate-driven DF process that successfully produced hydrogen under carbohydrate-limiting conditions using tequila vinasse as a substrate. Microbial responses to stepwise decreases in hydraulic retention time (HRT) from 24 to 4 h were assessed by using Illumina MiSeq sequencing. HRTs above 12 h and below 6 h led to a lower hydrogen production rate (HPR; 0.2–3.3 L/L-d) and process stability (HPR variations within 25–65%), which were associated with the presence of Acetobacter lovaniensis, Clostridium luticellari, Blautia coccoides, and the high abundance of propionate and lactate. Interestingly, transient conditions from unsteady-to-steady state occurred at an HRT of 12 h, where species richness and evenness decreased remarkably. Accordingly, HRTs between 12 and 6 h resulted in higher HPRs of up to 11.7 ± 0.7 L/L-d with HPR variations of less than 10%, which closely matched with the dominance of Clostridium sp., and butyrate and acetate as the main aqueous products. Overall, the results indicate that the successfulness of exploiting the ‘unwanted’ LAB proliferation through lactate-driven DF processes requires the enrichment of lactate-consuming and hydrogen-producing bacteria, which entails the selection of proper biocatalysts and operating conditions/strategies such as the operation of DF reactors under carbohydrate-limiting conditions and low HRTs. 相似文献
210.
Birgit Böhme Rene Kretzschmar Yvonne Schneider Petra Fiala Harald Rohm 《Journal of the American Oil Chemists' Society》2012,89(3):447-454
Commercial praline shells made from dark chocolate were filled with a mixture of invert sugar syrup, wine distillate and sucrose,
which was adjusted to a viscosity of approximately 4 Pa·s by addition of pregelatinized starch. The pralines which also contained
malt extract were subjected to storage at 20 and 24 °C. The liquefaction rate induced by enzymes of the malt extract depended
on ethanol (0–15% w/w) and moisture content (approximately 30%) of the filling, and on storage temperature. The decay of apparent
viscosity immediately after adding malt extract was delayed when ethanol was present in the filling, implying that viscosity
stability after mixing and during subsequent processing is improved. Softening of the praline shells and fat bloom formation
also depended on the ethanol concentration of the filling. A cross-comparison with praline shells which were filled with pure
invert sugar syrup implies that the enzymes of the malt extract do not exhibit a negative influence on praline shell firmness.
Electron micrographs give evidence that ethanol in contact with chocolate causes structural damage which results in a partial
solubilization of praline shells. 相似文献